I read a sci-fi book about 30 years ago about a war with another race where a plant extract put the entire earth population asleep, except for one guy who used robots to create "ghosts" which scared the invading aliens and allowed the hero to enter a defense station and win the war. Any ideas on what it was called?
As long as "The Unaffected" fought the Llralans, Earth would not die in its sleep! Lulled into a coma by the exotic fumes from a strange plant, the people of Earth experienced terrible dreams while orange-skinned invaders quietly began taking control. But even as the planet slumbered to its downfall, a few Terrans miraculously remained awake. These were "The Unaffected" - men like Brad Donovan and Jimmy Rierson who battled the invaders with every weapon of technology and psychology at their disposal to prevent Earth from becoming a land of the living dead.
Definitely "Sleeping Planet". Earth and colonies are in an interstellar war against the Llralans (never can spell that). They put the populations of Earth, Mars and Venus to sleep and land troops and threaten to kill the populations of all 3 planets if the Terran forces don't make concessions. Donovan in fact does have prosthetic legs, if memory servers. Rierson convinces the aliens her is the ghost of "Gremper" (Grandpa) preying on the superstitious soldiers guarding the planet.